ladybird/AK/Tests/TestRedBlackTree.cpp
Idan Horowitz e962254eb2 AK: Implement RedBlackTree container
This container is based on a balanced binary search tree, and as such
allows for O(logn) worst-case insertion, removal, and search, as well
as O(n) sorted iteration.
2021-04-12 18:03:44 +02:00

110 lines
3.3 KiB
C++

/*
* Copyright (c) 2021, Idan Horowitz <idan.horowitz@gmail.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/TestSuite.h>
#include <AK/Random.h>
#include <AK/RedBlackTree.h>
TEST_CASE(construct)
{
RedBlackTree<int, int> empty;
EXPECT(empty.is_empty());
EXPECT(empty.size() == 0);
}
TEST_CASE(ints)
{
RedBlackTree<int, int> ints;
ints.insert(1, 10);
ints.insert(3, 20);
ints.insert(2, 30);
EXPECT_EQ(ints.size(), 3u);
EXPECT_EQ(*ints.find(3), 20);
EXPECT_EQ(*ints.find(2), 30);
EXPECT_EQ(*ints.find(1), 10);
EXPECT(!ints.remove(4));
EXPECT(ints.remove(2));
EXPECT(ints.remove(1));
EXPECT(ints.remove(3));
EXPECT_EQ(ints.size(), 0u);
}
TEST_CASE(largest_smaller_than)
{
RedBlackTree<int, int> ints;
ints.insert(1, 10);
ints.insert(11, 20);
ints.insert(21, 30);
EXPECT_EQ(ints.size(), 3u);
EXPECT_EQ(*ints.find_largest_not_above(3), 10);
EXPECT_EQ(*ints.find_largest_not_above(17), 20);
EXPECT_EQ(*ints.find_largest_not_above(22), 30);
EXPECT_EQ(ints.find_largest_not_above(-5), nullptr);
}
TEST_CASE(key_ordered_iteration)
{
constexpr auto amount = 10000;
RedBlackTree<int, size_t> test;
Array<int, amount> keys {};
// generate random key order
for (int i = 0; i < amount; i++) {
keys[i] = i;
}
for (size_t i = 0; i < amount; i++) {
swap(keys[i], keys[get_random<size_t>() % amount]);
}
// insert random keys
for (size_t i = 0; i < amount; i++) {
test.insert(keys[i], keys[i]);
}
// check key-ordered iteration
size_t index = 0;
for (auto& value : test) {
EXPECT(value == index++);
}
// ensure we can remove all of them (aka, tree structure is not destroyed somehow)
for (size_t i = 0; i < amount; i++) {
EXPECT(test.remove(i));
}
}
TEST_CASE(clear)
{
RedBlackTree<size_t, size_t> test;
for (size_t i = 0; i < 1000; i++) {
test.insert(i, i);
}
test.clear();
EXPECT_EQ(test.size(), 0u);
}
TEST_MAIN(RedBlackTree)